The book "The Puppet Masters" was written by whom?

The book “The Puppet Masters” was written by Robert A. Heinlein. First published in 1951, it is a science-fiction novel about parasitic alien organisms that take control of human bodies and secretly prepare Earth for invasion.

The story follows Sam, an intelligence agent, his older colleague Mary, and their superior known as the Old Man. Together, they investigate strange events in the American Midwest and uncover the “puppets,” slug-like creatures that attach themselves to human hosts and control their actions.

Heinlein wrote the novel during the early Cold War, and its themes reflect the political anxiety of the period. The hidden invaders, secrecy, surveillance, and fear of infiltration echo concerns associated with the Second Red Scare and McCarthy-era America. The novel also draws on the era's fascination with flying saucers and extraterrestrial threats.

“The Puppet Masters” was originally serialized in Galaxy Science Fiction in 1951 before appearing as a book from Doubleday. It is often grouped with Heinlein's major early works, alongside “Rocket Ship Galileo,” “Red Planet,” and “Stranger in a Strange Land.” The title is sometimes confused with later alien-invasion novels, but Heinlein's novel is specifically a 1951 work about mind-controlling parasites.